I am developing a plugin for Craft 3. And I am trying to add some content to all pages in the CMS using this plugin. How can I do that? Is there a method or class call I can use for this? I am not sure where this is mentioned in the docs either.
Basically I want to add a few lines of HTML, CSS and JS in all the pages of the CMS if my plugin is installed and enabled in that Craft installation. Any ideas, anyone?